feat(aws): add AWS Lambda stream handler for serverless deployment

Author: xanderbilla

src/main/java/com/example/demo/handler/StreamLambdaHandler.java

@@ -0,0 +1,34 @@
+package com.example.demo.handler;
+
+import com.amazonaws.serverless.exceptions.ContainerInitializationException;
+import com.amazonaws.serverless.proxy.model.AwsProxyRequest;
+import com.amazonaws.serverless.proxy.model.AwsProxyResponse;
+import com.amazonaws.serverless.proxy.spring.SpringBootLambdaContainerHandler;
+import com.amazonaws.services.lambda.runtime.Context;
+import com.amazonaws.services.lambda.runtime.RequestStreamHandler;
+import com.example.demo.DemoApplication;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+public class StreamLambdaHandler implements RequestStreamHandler {
+    
+    private static SpringBootLambdaContainerHandler<AwsProxyRequest, AwsProxyResponse> handler;
+    
+    static {
+        try {
+            handler = SpringBootLambdaContainerHandler.getAwsProxyHandler(DemoApplication.class);
+        } catch (ContainerInitializationException e) {
+            // If we fail here, re-throw the exception to force another cold start
+            e.printStackTrace();
+            throw new RuntimeException("Could not initialize Spring Boot application", e);
+        }
+    }
+    
+    @Override
+    public void handleRequest(InputStream inputStream, OutputStream outputStream, Context context)
+            throws IOException {
+        handler.proxyStream(inputStream, outputStream, context);
+    }
+}